setup.c

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/*
 *  linux/arch/i386/kernel/setup.c
 *
 *  Copyright (C) 1995  Linus Torvalds
 *
 *  Enhanced CPU type detection by Mike Jagdis, Patrick St. Jean
 *  and Martin Mares, November 1997.
 *
 *  Force Cyrix 6x86(MX) and M II processors to report MTRR capability
 *  and Cyrix "coma bug" recognition by
 *      Zolt醤 B鰏z鰎m閚yi <[e-mail]> February 1999.
 * 
 *  Force Centaur C6 processors to report MTRR capability.
 *      Bart Hartgers <[e-mail]>, May 1999.
 *
 *  Intel Mobile Pentium II detection fix. Sean Gilley, June 1999.
 *
 *  IDT Winchip tweaks, misc clean ups.
 *	Dave Jones <[e-mail]>, August 1999
 *
 *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
 *
 *  Better detection of Centaur/IDT WinChip models.
 *      Bart Hartgers <[e-mail]>, August 1999.
 *
 *  Memory region support
 *	David Parsons <[e-mail]>, July-August 1999
 *
 *  Cleaned up cache-detection code
 *	Dave Jones <[e-mail]>, October 1999
 *
 *	Added proper L2 cache detection for Coppermine
 *	Dragan Stancevic <[e-mail]>, October 1999
 *
 *  Added the original array for capability flags but forgot to credit 
 *  myself :) (~1998) Fixed/cleaned up some cpu_model_info and other stuff
 *  	Jauder Ho <[e-mail]>, January 2000
 *
 *  Detection for Celeron coppermine, identify_cpu() overhauled,
 *  and a few other clean ups.
 *  Dave Jones <[e-mail]>, April 2000
 *
 *  Pentium III FXSR, SSE support
 *  General FPU state handling cleanups
 *	Gareth Hughes <[e-mail]>, May 2000
 *
 *  Added proper Cascades CPU and L2 cache detection for Cascades
 *  and 8-way type cache happy bunch from Intel:^)
 *  Dragan Stancevic <[e-mail]>, May 2000 
 *
 *  Forward port AMD Duron errata T13 from 2.2.17pre
 *  Dave Jones <[e-mail]>, August 2000
 *
 *  Forward port lots of fixes/improvements from 2.2.18pre
 *  Cyrix III, Pentium IV support.
 *  Dave Jones <[e-mail]>, October 2000
 *
 *  Massive cleanup of CPU detection and bug handling;
 *  Transmeta CPU detection,
 *  H. Peter Anvin <[e-mail]>, November 2000
 */

/*
 * This file handles the architecture-dependent parts of initialization
 */

#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/malloc.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/tty.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/config.h>
#include <linux/init.h>
#include <linux/apm_bios.h>
#ifdef CONFIG_BLK_DEV_RAM
#include <linux/blk.h>
#endif
#include <linux/highmem.h>
#include <linux/bootmem.h>
#include <asm/processor.h>
#include <linux/console.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/cobalt.h>
#include <asm/msr.h>
#include <asm/desc.h>
#include <asm/e820.h>
#include <asm/dma.h>
#include <asm/mpspec.h>
#include <asm/mmu_context.h>
/*
 * Machine setup..
 */

char ignore_irq13;		/* set if exception 16 works */
struct cpuinfo_x86 boot_cpu_data = { 0, 0, 0, 0, -1, 1, 0, 0, -1 };

unsigned long mmu_cr4_features;

/*
 * Bus types ..
 */
#ifdef CONFIG_EISA
int EISA_bus;
#endif
int MCA_bus;

/* for MCA, but anyone else can use it if they want */
unsigned int machine_id;
unsigned int machine_submodel_id;
unsigned int BIOS_revision;
unsigned int mca_pentium_flag;

/*
 * Setup options
 */
struct drive_info_struct { char dummy[32]; } drive_info;
struct screen_info screen_info;
struct apm_info apm_info;
struct sys_desc_table_struct {
	unsigned short length;
	unsigned char table[0];
};

struct e820map e820;

unsigned char aux_device_present;

#ifdef CONFIG_BLK_DEV_RAM
extern int rd_doload;		/* 1 = load ramdisk, 0 = don't load */
extern int rd_prompt;		/* 1 = prompt for ramdisk, 0 = don't prompt */
extern int rd_image_start;	/* starting block # of image */
#endif

extern int root_mountflags;
extern char _text, _etext, _edata, _end;
extern unsigned long cpu_khz;

static int disable_x86_serial_nr __initdata = 1;

/*
 * This is set up by the setup-routine at boot-time
 */
#define PARAM	((unsigned char *)empty_zero_page)
#define SCREEN_INFO (*(struct screen_info *) (PARAM+0))
#define EXT_MEM_K (*(unsigned short *) (PARAM+2))
#define ALT_MEM_K (*(unsigned long *) (PARAM+0x1e0))
#define E820_MAP_NR (*(char*) (PARAM+E820NR))
#define E820_MAP    ((struct e820entry *) (PARAM+E820MAP))
#define APM_BIOS_INFO (*(struct apm_bios_info *) (PARAM+0x40))
#define DRIVE_INFO (*(struct drive_info_struct *) (PARAM+0x80))
#define SYS_DESC_TABLE (*(struct sys_desc_table_struct*)(PARAM+0xa0))
#define MOUNT_ROOT_RDONLY (*(unsigned short *) (PARAM+0x1F2))
#define RAMDISK_FLAGS (*(unsigned short *) (PARAM+0x1F8))
#define ORIG_ROOT_DEV (*(unsigned short *) (PARAM+0x1FC))
#define AUX_DEVICE_INFO (*(unsigned char *) (PARAM+0x1FF))
#define LOADER_TYPE (*(unsigned char *) (PARAM+0x210))
#define KERNEL_START (*(unsigned long *) (PARAM+0x214))
#define INITRD_START (*(unsigned long *) (PARAM+0x218))
#define INITRD_SIZE (*(unsigned long *) (PARAM+0x21c))
#define COMMAND_LINE ((char *) (PARAM+2048))
#define COMMAND_LINE_SIZE 256

#define RAMDISK_IMAGE_START_MASK  	0x07FF
#define RAMDISK_PROMPT_FLAG		0x8000
#define RAMDISK_LOAD_FLAG		0x4000	

#ifdef	CONFIG_VISWS
char visws_board_type = -1;
char visws_board_rev = -1;

#define	PIIX_PM_START		0x0F80

#define	SIO_GPIO_START		0x0FC0

#define	SIO_PM_START		0x0FC8

#define	PMBASE			PIIX_PM_START
#define	GPIREG0			(PMBASE+0x30)
#define	GPIREG(x)		(GPIREG0+((x)/8))
#define	PIIX_GPI_BD_ID1		18
#define	PIIX_GPI_BD_REG		GPIREG(PIIX_GPI_BD_ID1)

#define	PIIX_GPI_BD_SHIFT	(PIIX_GPI_BD_ID1 % 8)

#define	SIO_INDEX	0x2e
#define	SIO_DATA	0x2f

#define	SIO_DEV_SEL	0x7
#define	SIO_DEV_ENB	0x30
#define	SIO_DEV_MSB	0x60
#define	SIO_DEV_LSB	0x61

#define	SIO_GP_DEV	0x7

#define	SIO_GP_BASE	SIO_GPIO_START
#define	SIO_GP_MSB	(SIO_GP_BASE>>8)
#define	SIO_GP_LSB	(SIO_GP_BASE&0xff)

#define	SIO_GP_DATA1	(SIO_GP_BASE+0)

#define	SIO_PM_DEV	0x8

#define	SIO_PM_BASE	SIO_PM_START
#define	SIO_PM_MSB	(SIO_PM_BASE>>8)
#define	SIO_PM_LSB	(SIO_PM_BASE&0xff)
#define	SIO_PM_INDEX	(SIO_PM_BASE+0)
#define	SIO_PM_DATA	(SIO_PM_BASE+1)

#define	SIO_PM_FER2	0x1

#define	SIO_PM_GP_EN	0x80

static void
visws_get_board_type_and_rev(void)
{
	int raw;

	visws_board_type = (char)(inb_p(PIIX_GPI_BD_REG) & PIIX_GPI_BD_REG)
							 >> PIIX_GPI_BD_SHIFT;
/*
 * Get Board rev.
 * First, we have to initialize the 307 part to allow us access
 * to the GPIO registers.  Let's map them at 0x0fc0 which is right
 * after the PIIX4 PM section.
 */
	outb_p(SIO_DEV_SEL, SIO_INDEX);
	outb_p(SIO_GP_DEV, SIO_DATA);	/* Talk to GPIO regs. */
    
	outb_p(SIO_DEV_MSB, SIO_INDEX);
	outb_p(SIO_GP_MSB, SIO_DATA);	/* MSB of GPIO base address */

	outb_p(SIO_DEV_LSB, SIO_INDEX);
	outb_p(SIO_GP_LSB, SIO_DATA);	/* LSB of GPIO base address */

	outb_p(SIO_DEV_ENB, SIO_INDEX);
	outb_p(1, SIO_DATA);		/* Enable GPIO registers. */
    
/*
 * Now, we have to map the power management section to write
 * a bit which enables access to the GPIO registers.
 * What lunatic came up with this shit?
 */
	outb_p(SIO_DEV_SEL, SIO_INDEX);
	outb_p(SIO_PM_DEV, SIO_DATA);	/* Talk to GPIO regs. */

	outb_p(SIO_DEV_MSB, SIO_INDEX);
	outb_p(SIO_PM_MSB, SIO_DATA);	/* MSB of PM base address */
    
	outb_p(SIO_DEV_LSB, SIO_INDEX);
	outb_p(SIO_PM_LSB, SIO_DATA);	/* LSB of PM base address */

	outb_p(SIO_DEV_ENB, SIO_INDEX);
	outb_p(1, SIO_DATA);		/* Enable PM registers. */
    
/*
 * Now, write the PM register which enables the GPIO registers.
 */
	outb_p(SIO_PM_FER2, SIO_PM_INDEX);
	outb_p(SIO_PM_GP_EN, SIO_PM_DATA);
    
/*
 * Now, initialize the GPIO registers.
 * We want them all to be inputs which is the
 * power on default, so let's leave them alone.
 * So, let's just read the board rev!
 */
	raw = inb_p(SIO_GP_DATA1);
	raw &= 0x7f;	/* 7 bits of valid board revision ID. */

	if (visws_board_type == VISWS_320) {
		if (raw < 0x6) {
			visws_board_rev = 4;
		} else if (raw < 0xc) {
			visws_board_rev = 5;
		} else {
			visws_board_rev = 6;
	
		}
	} else if (visws_board_type == VISWS_540) {
			visws_board_rev = 2;
		} else {
			visws_board_rev = raw;
		}

		printk("Silicon Graphics %s (rev %d)\n",
			visws_board_type == VISWS_320 ? "320" :
			(visws_board_type == VISWS_540 ? "540" :
					"unknown"),
					visws_board_rev);
	}
#endif


static char command_line[COMMAND_LINE_SIZE];
       char saved_command_line[COMMAND_LINE_SIZE];

struct resource standard_io_resources[] = {
	{ "dma1", 0x00, 0x1f, IORESOURCE_BUSY },
	{ "pic1", 0x20, 0x3f, IORESOURCE_BUSY },
	{ "timer", 0x40, 0x5f, IORESOURCE_BUSY },
	{ "keyboard", 0x60, 0x6f, IORESOURCE_BUSY },
	{ "dma page reg", 0x80, 0x8f, IORESOURCE_BUSY },
	{ "pic2", 0xa0, 0xbf, IORESOURCE_BUSY },
	{ "dma2", 0xc0, 0xdf, IORESOURCE_BUSY },
	{ "fpu", 0xf0, 0xff, IORESOURCE_BUSY }
};

#define STANDARD_IO_RESOURCES (sizeof(standard_io_resources)/sizeof(struct resource))

static struct resource code_resource = { "Kernel code", 0x100000, 0 };
static struct resource data_resource = { "Kernel data", 0, 0 };
static struct resource vram_resource = { "Video RAM area", 0xa0000, 0xbffff, IORESOURCE_BUSY };

/* System ROM resources */
#define MAXROMS 6
static struct resource rom_resources[MAXROMS] = {
	{ "System ROM", 0xF0000, 0xFFFFF, IORESOURCE_BUSY },
	{ "Video ROM", 0xc0000, 0xc7fff, IORESOURCE_BUSY }
};

#define romsignature(x) (*(unsigned short *)(x) == 0xaa55)

static void __init probe_roms(void)
{
	int roms = 1;
	unsigned long base;
	unsigned char *romstart;

	request_resource(&iomem_resource, rom_resources+0);

	/* Video ROM is standard at C000:0000 - C7FF:0000, check signature */
	for (base = 0xC0000; base < 0xE0000; base += 2048) {
		romstart = bus_to_virt(base);
		if (!romsignature(romstart))
			continue;
		request_resource(&iomem_resource, rom_resources + roms);
		roms++;
		break;
	}

	/* Extension roms at C800:0000 - DFFF:0000 */
	for (base = 0xC8000; base < 0xE0000; base += 2048) {
		unsigned long length;

		romstart = bus_to_virt(base);
		if (!romsignature(romstart))
			continue;
		length = romstart[2] * 512;
		if (length) {
			unsigned int i;
			unsigned char chksum;

			chksum = 0;
			for (i = 0; i < length; i++)
				chksum += romstart[i];

			/* Good checksum? */
			if (!chksum) {
				rom_resources[roms].start = base;
				rom_resources[roms].end = base + length - 1;
				rom_resources[roms].name = "Extension ROM";
				rom_resources[roms].flags = IORESOURCE_BUSY;

				request_resource(&iomem_resource, rom_resources + roms);
				roms++;
				if (roms >= MAXROMS)
					return;
			}
		}
	}

	/* Final check for motherboard extension rom at E000:0000 */
	base = 0xE0000;
	romstart = bus_to_virt(base);

	if (romsignature(romstart)) {
		rom_resources[roms].start = base;
		rom_resources[roms].end = base + 65535;
		rom_resources[roms].name = "Extension ROM";
		rom_resources[roms].flags = IORESOURCE_BUSY;

		request_resource(&iomem_resource, rom_resources + roms);
	}
}

void __init add_memory_region(unsigned long long start,
                                  unsigned long long size, int type)
{
	int x = e820.nr_map;

	if (x == E820MAX) {
	    printk("Ooops! Too many entries in the memory map!\n");
	    return;
	}

	e820.map[x].addr = start;
	e820.map[x].size = size;
	e820.map[x].type = type;
	e820.nr_map++;
} /* add_memory_region */

#define E820_DEBUG	1

static void __init print_memory_map(char *who)
{
	int i;

	for (i = 0; i < e820.nr_map; i++) {
		printk(" %s: %016Lx @ %016Lx ", who,
			e820.map[i].size, e820.map[i].addr);
		switch (e820.map[i].type) {
		case E820_RAM:	printk("(usable)\n");
				break;
		case E820_RESERVED:
				printk("(reserved)\n");
				break;
		case E820_ACPI:
				printk("(ACPI data)\n");
				break;
		case E820_NVS:
				printk("(ACPI NVS)\n");
				break;
		default:	printk("type %lu\n", e820.map[i].type);
				break;
		}
	}
}

/*
 * Copy the BIOS e820 map into a safe place.
 *
 * Sanity-check it while we're at it..
 *
 * If we're lucky and live on a modern system, the setup code
 * will have given us a memory map that we can use to properly
 * set up memory.  If we aren't, we'll fake a memory map.
 *
 * We check to see that the memory map contains at least 2 elements
 * before we'll use it, because the detection code in setup.S may
 * not be perfect and most every PC known to man has two memory
 * regions: one from 0 to 640k, and one from 1mb up.  (The IBM
 * thinkpad 560x, for example, does not cooperate with the memory
 * detection code.)
 */
static int __init copy_e820_map(struct e820entry * biosmap, int nr_map)
{
	/* Only one memory region (or negative)? Ignore it */
	if (nr_map < 2)
		return -1;

	do {
		unsigned long long start = biosmap->addr;
		unsigned long long size = biosmap->size;
		unsigned long long end = start + size;
		unsigned long type = biosmap->type;

		/* Overflow in 64 bits? Ignore the memory map. */
		if (start > end)
			return -1;

		/*
		 * Some BIOSes claim RAM in the 640k - 1M region.
		 * Not right. Fix it up.
		 */
		if (type == E820_RAM) {
			if (start < 0x100000ULL && end > 0xA0000ULL) {
				if (start < 0xA0000ULL)
					add_memory_region(start, 0xA0000ULL-start, type);
				if (end <= 0x100000ULL)
					continue;
				start = 0x100000ULL;
				size = end - start;
			}
		}
		add_memory_region(start, size, type);
	} while (biosmap++,--nr_map);
	return 0;
}

/*
 * Do NOT EVER look at the BIOS memory size location.
 * It does not work on many machines.
 */
#define LOWMEMSIZE()	(0x9f000)

void __init setup_memory_region(void)
{
	char *who = "BIOS-e820";

	/*
	 * Try to copy the BIOS-supplied E820-map.
	 *
	 * Otherwise fake a memory map; one section from 0k->640k,
	 * the next section from 1mb->appropriate_mem_k
	 */
	if (copy_e820_map(E820_MAP, E820_MAP_NR) < 0) {
		unsigned long mem_size;

		/* compare results from other methods and take the greater */
		if (ALT_MEM_K < EXT_MEM_K) {
			mem_size = EXT_MEM_K;
			who = "BIOS-88";
		} else {
			mem_size = ALT_MEM_K;
			who = "BIOS-e801";
		}

		e820.nr_map = 0;
		add_memory_region(0, LOWMEMSIZE(), E820_RAM);
		add_memory_region(HIGH_MEMORY, (mem_size << 10) - HIGH_MEMORY, E820_RAM);
  	}
	printk("BIOS-provided physical RAM map:\n");
	print_memory_map(who);
} /* setup_memory_region */


static inline void parse_mem_cmdline (char ** cmdline_p)
{
	char c = ' ', *to = command_line, *from = COMMAND_LINE;
	int len = 0;
	int usermem = 0;

	/* Save unparsed command line copy for /proc/cmdline */
	memcpy(saved_command_line, COMMAND_LINE, COMMAND_LINE_SIZE);
	saved_command_line[COMMAND_LINE_SIZE-1] = '\0';

	for (;;) {
		/*
		 * "mem=nopentium" disables the 4MB page tables.
		 * "mem=XXX[kKmM]" defines a memory region from HIGH_MEM
		 * to <mem>, overriding the bios size.
		 * "mem=XXX[KkmM]@XXX[KkmM]" defines a memory region from
		 * <start> to <start>+<mem>, overriding the bios size.
		 */
		if (c == ' ' && !memcmp(from, "mem=", 4)) {
			if (to != command_line)
				to--;
			if (!memcmp(from+4, "nopentium", 9)) {
				from += 9+4;
				clear_bit(X86_FEATURE_PSE, &boot_cpu_data.x86_capability);
			} else if (!memcmp(from+4, "exactmap", 8)) {
				from += 8+4;
				e820.nr_map = 0;
				usermem = 1;
			} else {
				/* If the user specifies memory size, we
				 * blow away any automatically generated
				 * size
				 */
				unsigned long start_at, mem_size;
 
				if (usermem == 0) {
					/* first time in: zap the whitelist
					 * and reinitialize it with the
					 * standard low-memory region.
					 */
					e820.nr_map = 0;
					usermem = 1;